Manipulate track lists (track)

move option

This option changes the time of all trackpoints. This might be useful if
your track must be moved by one or more hours because of an incorrect
time zone.

Example 4.8. Time-shifting a track with the track filter

The following command line will shift all tracks to be one hour later.

gpsbabel -t -i gpx -f in.gpx -x track,move=+1h -o gpx -F out.gpx

pack option

Pack all tracks into one.

This option causes all tracks to be appended to one another to form a single
track. This option does not work if any two tracks overlap in time; in that
case, consider using the merge option.

This option is most useful for rejoining tracks that might have
been interrupted by an equipment malfunction or an overnight stop.

If no other option is given to the track filter, this option is assumed.

split option

Split by date or time interval (see README).

The input track will be split into several tracks
depending on date of track points. If there is more than one
track, use the pack option before before using this. To
split a single tracks into separate tracks for each day and
name them, use this:

Additionally you can add an interval to the split
option. With this the track will be split if the time
between two points is greater than this parameter. The
interval must be numeric and can be int days, hours, minutes
or seconds, expressed as one of the character "d", "h", "m",
or "s". If no trailing character is present, the units are
assumed to be in seconds.

For example, to split a track based on an four hour
interval, use this:

sdistance option

Split by distance.

The input track will be split into several tracks
if the distance between successive track points
is greater than the distance given as a parameter.
The distance must be numeric and can be in miles or kilometers,
expressed as one of the character "k", or "m".
If sdistance is given no parameters, this option has the same
effect as the split option without parameters. If there is more
than one track,
use the pack option before before using this.

For example, to split the track if the distance between
points is greater than 100 meters, use this:

The sdistance option can be combined with the split option.
The track then will be split only if both time and distance
interval exceeds the supplied values. This technique can be used to
filter out gaps from
the tracklog. The gap is kept only if the gps device is without
signal for longer time than that given and during that time it moves
a distance over that given.
This example splits the track
if the device is without signal for at least 5 minutes
and during this time moves more than 300 meters:

start option

This option is used along with the stop to discard
trackpoints that were recorded outside of a specific period of time.
This option specifies the beginning of the time period.

If this option is not specified, the time period is assumed to begin at the
dawn of time or January 1, 1970, whichever was later. The time for this
option is expressed in UTC.

The value of this option must be in the form of YYYYMMDDHHMMSS, but it is
not necessary to specify the smaller time units if they are not needed.
That is, if you only care about points logged between 10 AM and 6 PM on a
given date, you need not specify the minutes or seconds.

Example 4.10. Extracting a period of time with the track filter

To get only the parts of a track that were mapped on 20 July 2005
between 10 AM and 6 PM, use this command line:

stop option

This option is used in conjunction with the start option to
discard all trackpoints outside of a given period of time. This option
defines the end of the time period.

If this option is not specified, the time period is assumed to end at the
end of civilization as we know it or the year 2038, whichever comes first.
The time for this option is expressed in UTC.

See the start option for the format of this value and an
example of usage.

title option

Basic title for new track(s).

This option specifies a title for tracks generated by the track filter.
By default, the title of the new track is composed of the start time of
the track appended to this value.

If this value contains a percent (%) character, it is treated as a format
string for the POSIX strftime function, allowing custom time-based
track names.

fix option

Synthesize GPS fixes (PPS, DGPS, 3D, 2D, NONE).

This option sets the GPS fix status for all trackpoints to the specified
value. Valid values for this option are PPS, DGPS, 3D, 2D, or NONE.

This option is most useful when converting from a format that doesn't
contain GPS fix status to one that requires it.

course option

Synthesize course.

This option computes (or recomputes) a value for the GPS heading at each
trackpoint. This is most useful with trackpoints from formats that don't
support heading information or for trackpoints synthesized by the
interpolate
filter. The heading at each trackpoint is simply the course from the
previous trackpoint in the track. The first trackpoint in each track
is arbitrarily assigned a heading of 0 degrees.

speed option

Synthesize speed.

This option computes a value for the GPS speed at each trackpoint.
This is most useful with trackpoints from formats that don't support
speed information or for trackoints synthesized by the
interpolate
filter. The speed at each trackpoint is the average speed from the
previous trackpoint (distance divided by time). The first trackpoint
in each track is assigned a speed of "unknown."

seg2trk option

Split track at segment boundaries into multiple tracks.

This option splits tracks at segment boundaries into multiple tracks. This
is useful to restore the behaviour of GPSBabel versions up to 1.3.6 which
didn't support track segment markers and automatically put each segment into
a separate track.

trk2seg option

Merge tracks inserting segment separators at boundaries.

This option merges multiple tracks, inserting segment separators at
track boundaries. It expects the tracks to already be in the right order for
merging, i.e. it does not check timestamps and reorder track points so that
their timestamps are monotonically increasing.

segment option

segment tracks with abnormally long gaps.

faketime option

Add specified timestamp to each trackpoint.

This option assigns a time value to each trackpoint.

The value of this option must be in the form of fYYYYMMDDHHMMSS+SS.

The parameter f (force) is optional and means that the time value of each trackpoint is replaced.
If f is not specified, the time value of each trackpoint is only replaced when the trackpoint contains no time value.

YYYYMMDDHHMMSS is the pattern for the timestamp and is required.

The plus sign is the delimiter between the timestamp and the step time in seconds.
The first trackpoint receives the time value of the timestamp and
each following trackpoint receives the timestamp incremented by the step time.
The specification of the steptime is optional.

The parameter was added because some software products (e.g. garmin training center)
require a time value for each trackpoint.

Example 4.11. Replace time values of a track

Replace all time values with new time values.
Start at the 5 th of July, 2010 at 8 PM and
increment 2 seconds between each trackpoint: